Suturing of tissue during surgical procedures is time consuming and can be particularly challenging in difficult to access body regions and regions that have limited clearance, such as regions partially surrounded or covered by bone. For many surgical procedures, it is necessary to make a large opening in the human body to expose the area requiring surgical repair. However, in many cases, accessing the tissue in this manner is undesirable, increasing recovery time, and exposing the patient to greater risk of infection.
Suturing instruments (“suture passers” or “suturing devices”) have been developed to assist in accessing and treating internal body regions, and to generally assist a physician in repairing tissue. Although many such devices are available for endoscopic and/or percutaneous use, these devices suffer from a variety of problems, including limited ability to navigate and be operated within the tight confines of the body, risk of injury to adjacent structures, problems controlling the position and/or condition of the tissue before, during, and after passing the suture, and difficulties loading the suture into the device, particularly for threading multiple suture loops.
For example, some surgical instruments used in endoscopic procedures are limited by the manner in which they access the areas of the human body in need of repair. In particular, the instruments may not be able to access tissue or organs located deep within the body or that are in some way obstructed. In addition, many of the instruments are limited by the way they grasp tissue, apply a suture, or recapture the needle and suture. Furthermore, many of the instruments are complicated and expensive to use due to the numerous parts and/or subassemblies required to make them function properly. Suturing remains a delicate and time-consuming aspect of most surgeries, including those performed endoscopically.
The knee joint is one example of a tissue region that is notoriously difficult to access. For example, the meniscus is a C-shaped piece of fibrocartilage which is located at the peripheral aspect of the joint (e.g., the knee) between the condyles of the femur and the tibia on the lateral and medial sides of the knee. The central two-thirds of the meniscus has a limited blood supply while the peripheral one third typically has an excellent blood supply. Acute traumatic events commonly cause meniscus tears in younger patients while degenerative tears are more common in older patients as the menisci become increasingly brittle with age. Typically, when the meniscus is damaged, a torn piece of meniscus may move in an abnormal fashion inside the joint, which may lead to pain and loss of function of the joint. Early arthritis can also occur due to these tears as abnormal mechanical movement of torn meniscal tissue and the loss of the shock absorbing properties of the meniscus lead to destruction of the surrounding articular cartilage. Occasionally, it is possible to repair a torn meniscus. While this may be done arthroscopically, surgical repair using a suture has proven difficult to perform because of the hard-to-reach nature of the region and the difficulty in placing sutures in a way that compresses and secures the torn surfaces.
The meniscus of the knee is just one example of a tissue that is difficult to access so that appropriate suturing may be performed. FIG. 2 illustrate the anatomy of the meniscus in the context of a knee joint. As shown in FIG. 2 the capsule region (the outer edge region of the meniscus) is vascularized. Blood enters the meniscus from the menisculocapsular region 291 lateral to the meniscus. A typical meniscus has a flattened bottom 298 (inferior surface or side adjacent to the tibia) and a concave top 296 (superior surface or side, adjacent to the femur), and the outer cross-sectional shape may be somewhat triangular, with a meniscus tip region 294. The outer edge of the meniscus transitions into the capsule 291. The meniscus may include circumferential fibers extending along the curved length of the meniscus, as well as radial fibers, and more randomly distributed mesh network fibers. Because of the relative orientations and structures of these fibers, and the predominance of circumferential fibers, it may be beneficial to repair the meniscus by suturing radially (vertically) rather than longitudinally or horizontally, depending on the type of repair being performed. Most prior art devices for suturing or repairing the meniscus are only capable of reliably repairing vertical/longitudinal tears. Such devices are not typically useful for repairing radial or horizontal tears. Furthermore, prior art device mechanisms have a high inherent risk for iatrogenic injury to surrounding neurovascular structures and chondral surfaces.
Thus, there is a need for methods and apparatuses (e.g., devices and systems) for suturing tissue, particularly tissue in difficult to access regions of the body including the joints (shoulder, knee, etc.). In particularly, it has proven useful to provide a device that may simply and reliably reach and pass sutures within otherwise inaccessible tissue regions. Such devices should be extremely low profile, and may be adapted or otherwise configured to fit in the tight spaces of the joints. Finally, would be useful to provide suturing apparatuses that allow selective and specific penetration of the tissue by both the tissue penetrator (needle element) and a jaw so that complex (including right-angled) suturing patterns may be achieved.
Although a suture passers that may be preloaded or reloadable with one or more sutures have been suggested, these devices typically require manual loading, activation and control of the suture in order to operate. Suture passers that could pass two (or more) lengths of suture, including two or more portions of the same suture, without requiring manual loading or reloading, would be highly advantageous, as they could increase the ease of suturing and reduce the time required for surgical procedures, as well as elimination or reducing a possible source of operational error.
To address these needs, U.S. application Ser. No. 14/572,485 (incorporated by reference above) describes pre-loaded suture passers that may pass multiple lengths (bights) of one or more suture. Unfortunately, when passing multiple lengths of suture using a pre-loaded suture passer, one failure mode is the recapture or entangle the previously passed length of suture, when passing the second length of suture.
Described herein are preloaded suture passers, preloaded cartridges for suture passers, and methods of operating such apparatuses to repair tissue capable of automatically passing a preloaded length of suture and automatically preloading with a second length of suture, while preventing entanglement and/or entrapment of the first bight. These apparatuses (e.g., devices, including suture passers, and cartridges for suture passers, and systems of suture passers) and the methods of operating them described herein may be used to access difficult-to reach tissues.
The apparatuses and methods described herein may address the needs and potential benefits briefly discussed above.